Manufacture of chlorofluoroacetones



U ited States Patent ()ffii 2,807,646 Patented Sept. 24, 1957MANUFACTURE OF CHLOROFLUOROACETONES Charles B. Miller and Cyril Woolf,Morristown, N. J., assignors to Allied Chemical & Dye Corporation, NewYork, N. Y., a corporation of New York No Drawing. Application March 14,1955, Serial No. 494,238

6 Claims. (Cl. 260-593) This invention relates to organic fluorinecompounds, and is particularly directed to methods for making per-.chlorofluoroacetones and to certain perchlorofluoroacetone products.

In our copending applications Serial No. 411,028, filed February 17,1954 (now abandoned) and Serial No. 494,237, filed March 14, 1955, wehave disclosed and claimed perchlorofluoroacetonescontaining at leastone fluorine atom and at least one chlorine atomand processes for makingsuch materials. The present invention is directed to particularprocesses for making some of the foregoing and other similar products.The compounds disclosed herein are valuable chemical intermediates, andconstitute raw materials for manufacture of fluorine containing productsin operations not part of this invention.

Among other features, our copending application describes and claimsperchlorofluoroacetone product manufacture processes which compriseliquid phase fluorinationreactions involving use of pentavalent antimonyfluorochloride. While liquid phase reactions of the type indicated maybe practiced successfully on commercial scale, nevertheless liquid phaseprocesses utilizing antimony halide type fluorinating agents arecharacterized by'recognized disadvantages, among which are thecorrosiveness of the antimony halide fluorinating agents, difficultiesarising out of the use of a liquid fluorinating agent as distinguishedfrom a solid catalyst, and relatively highantimony halides volatilitywhich causes gas line plugging. Hence, objects of the present inventioninclude development of completely gas phase methods for preparingperchlorofluoroacetones by means of an advantageous solid catalyst.

The instant improvements provide for manufacture ofperchlorofluoroacetones containing at least one fluorine atom and atleast two chlorine atoms. It has been discovered, according to thepresent invention, that the hereindescribed perchlorofluoroacetones maybe made by contacting in gas phase a certain class of starting materialswith a solid zirconium fluoride (ZrFr) catalyst, which is substantiallynon-crystalline in structure, while in the presence of gaseoushydrofluoric acid.- Major aspects of this invention include discovery ofcertain new perchlorofluoroacetones, determination of a particular classof compounds which may be used as starting materials, and the discoveryof the fluorinating properties of a particular catalyst with respect tothe starting materials involved. Because of determination of thestarting materials and the conjunctive discovery of the catalyticproperties of the zirconium fluoride catalyst as to the indicatedstarting materials, it becomes possible to manufactureperchlorofluoroacetone products including certainperchlorofluoroacetones not heretofore known, and to make the sought-forproducts by a wholly gas phase procedure which does not causesubstantial decomposition of either starting materials or products.

Referringto suitable starting materials, it has been ascertained thatthe products of the invention may be obtained from a relatively specificclass of starting materials which do not contain hydrogen and hence aredefined herein as perhalogenated acetones. In the broader aspects, thestarting materials comprise perchloroor pets chlorofluoroacetonescontaining zero to not more than 3 fluorine atoms, and wherein-allhalogens are of the group consisting of chlorine and fluorine. In thepreferred embodiments of the invention, the starting material ishexachloroacetone, i. e. CC13.CO.CC13, a liquid under normal conditionshaving a boiling range of 202-204 C.

It is important that the invention starting materials should contain nohydrogen. It has been found that, when proceeding in accordance with theprocess aspects of the invention, any attempt to use starting materialscontaining any hydrogen, results in formation of substantially none ofthe herein sought-for products, but on the other hand causes vigorousdecomposition of the hydrogen-containing starting material withformation-of unwanted compounds such as phosgene, carbon monoxide,halogenated methane derivatives and resinous tars. Hence, startingmaterials of the invention are perhalogenated acetones containing nohydrogen. As toselection of suitable starting material, another factoris fluorine content. Whilestarting material containing some fluorine maybe employed, the materials utilized should contain not more than 3fluorine atoms, the balance of halogen being chlorine.

Representative examples of suitable starting materials are thosecompounds containing indicated limited amounts of fluorine such asmonofluoropentachloroacetone (CF Cl2.CO.CCls);difluorotetrachloroacetone,

(CFC12.CO.CFC12);

stood that if a compound such as monofluoropentachloroacetone isutilized as starting material, practice of the invention results in aproduct which contains at least 2 atoms of fluorine and may contain asmuch as 4 fluorine atoms. Similarly, if the starting material istrichlorotrifluoroacetone (CCI2F.CO.CC1F2), the product obtainedtherefrom contains more fluorine and may be tetrafluorodichloroacetone(CClF2.CO.CClF2). The current commercially important raw material mostadaptable for use as a starting material is hexachloroacetone, and thusfor convenience the invention is described herein largely in connectionwith use of hexachloroacetone as the starting material.

The zirconium fluorides used as catalysts according to the presentinvention have the property of catalyzing fluorination of the abovedescribed oxygen-containing starting materials to form theperhalogenated fluoroacetone products to such an extent that good yields(percentage of sought-for product recovered based on the tively largesize, i. e., not less than one thousand and usually'sev'eral thousandAngstrom units radius and above. Other forms of ZrF4 as describedherein, when examined by the highest powered optical microscope, appearto be of non-crystalline or amorphous structure. When these amorphous,by ordinary standards, zirconium fluorides are examined using X-raydiffraction technique, such materials are found to be bordering on theamorphous condition, and are extremely small, submicroscopic crystalswhich are designated in the art as crystallite. According to theinvention, the ZTF4 catalysts thereof are catalytically useable size(mesh) increments, e. g. granules or pellets, which are constituted ofsuch amorphous zirconium fluoride having crystallite size. The desiredcatalytic activity prevails in zirconium fluorides of crystallite sizeof about 400 Angstrom units radius or below. As crystallite sizedecreases below this value, desired catalytic activity increases andparticularly preferred zirconium fluorides include those havingcrystallite size of about 150 A. and below, as determined by X-raydiffraction technique.

The scope of the invention includes substantially anhydrous zirconiumfluorides (ZrFr) having the indicated crystallite size, and providedsuch fluorides are derived by reaction of substantially anhydrous ZrCl-rand substantially anhydrous hydrogen fluoride. The improved catalyticmaterial employed is prepared by treating ZrCl4, which. is preferably asanhydrous as commercially feasible and preferably in pure form but maysuitably be of commercial or technical grade, with preferably excessquantities of inorganic fluorinating agent reactive therewith underconditions such that no liquidwater is present in the reactingmaterials. For example, catalysts may be prepared by treating solidsubstantially anhydrous zirconium chloride (intended herein to designateZrCl4 and not other forms of zirconium chloride) with gaseoussubstantially anhydrous HF. In a gas phase fluorination oper ation,using HF, temperatures may be anything from above the vaporization pointof HF up to about 250 C. at which temperature e. g. anhydrous ZTCL;begins to sublime appreciably. If desired, the reaction may be carriedout with fluorinating agent in the liquid phase. In the catalystsynthesis reaction, HF displaces HCl causing transformation of ZrClrtoZrF4. To conditionthe material for better catalytic use, the resultingzirconium fluoride may be heated in an anhydrous atmosphere at elevatedtemperature, i. e., temperature at which conditioning or,activationtakes place. The finished catalyst is then recovered. Heating the ZrFrin a stream of dry nitrogen or anhydrous HF gas for about one to fourhours at temperatures of about 300-350 C. or four to six hours at250-300 C. is ordinarily suitable for this purpose. In somecircumstances, the catalyst may be activatedby heating the ZrFr in astream of free oxygencontaining gas such as oxygen or air at about400-500" C. for approximately 30 minutes to eight and one-half hours,depending mostly on the oxygen content of the treatment gas, in whichcase conditioning with dry nitrry gen or HP gas as above mentioned maybe omitted.

Zirconiumfluorides prepared by the above described method of treatinganhydrous ZrCl-r with substantially anhydrous HF have been found to becomposed of crystallites of size below about 400 A., and generallysubstantially :below 120 A. as is desired for use in the invention. Gasphase preparation of catalyst is illustrated in the following example,in which parts and percentages, unless otherwise noted, are on a weightbasis.

EXAMPLE A 180 parts of 4 to 14 mesh anhydrous zirconium tetrachloride ofcommercial grade were charged to a one inch I. D. tubular nickel reactorprovided with inlet and outlet connections for a gas stream and meansfor externally cooling the reactor by blasts of air. An externallydisposed electrical resistanceheater was also supplied to furnish heatto the reactor when needed. Gaseous anhydrous HF, initially at the rateof 20 parts per hour, was passed through the reactor while maintainingthe maximum internal temperature in the reactor in the range of 6070 C.by adjusting the extent of external cooling. Reaction of ZrCl-r and HPto form ZrFi and HCl was.

v effected.

Means were provided for sampling the reactor effluent gas to determinethe presence of HF and/or HCl. Initially, the point of maximum reactiontemperature was near the upstream end of the bed of solid zirconiumchloride. Exit gas from the reactor was periodically sampled and whenthe evolution of HCl began to slacken and HF began to appear, thereaction temperature was gradually raised to 200 C. After 5 hoursreaction, the reactor effluent gas contained only HF and wassubstantially free of HCl. parts of zirconium fluoride, containing 98%ZIFd and less than 0.5% chlorine, in hard granular form and havingsubstantially the same mesh size as the initial zirconium chloride, wereobtained. An X-ray diffraction pattern of zirconium fluoride catalyst soprepared showed that the material, constituting the approximate 4-14mesh catalyst, had average crystallite size of about 50 Angstrom unitsradius, i. e. the crystallite size was so small as to be indicative ofamorphous structure.

If, in the gas-phase operation such as just detailed, the ZrClt isinitially in very fine or powdery form, prior to HF gassing the materialmay be pelleted to c. g. 4-25 mesh size, in which case pe'lleting shouldbe done prefer,- ably under conditions as anhydrous as feasible.

Another suitable and convenient means for preparing the zirconiumfluoride catalyst is to add solid anhydrous ZrClr to an excess ofliquefied anhydrous hydrofluoric acid in a cooled container and, aftercomplete addition of the ZrClr, mildly agitate the mixture untilreaction is substantially complete. The ZrRi so prepared may be thenconditioned or activated as outlined above. Following is an example inwhich parts and percentages are on a weight basis, illustratingpreparation of ZrFr catalyst according to the latter wet method.

EXAMPLE B parts of granular (4 to 14 mesh) anhydrous ZrCl4 of commercialgrade were added in small portions to liquid anhydrous hydrofluoric'acidcontained in an externally cooled vessel. Vigorous exothermic reactiontook place and additional amounts of liquid anhydrous HF were added asneeded to maintain an excess thereof. After all the zirconium chloridehad been added, the mixture was stirred to promote residual reaction.When reaction of zirconium chloride appeared complete, the mass wasmixed and stirred with additional liquid hydrofluoric acid and excess HFwas removed by slowly boiling the mixture. 125 parts of anhydrouszirconium fluoride of about 420 mesh size having greater than 98% ZrF4content and containing less than 0.5% chlorine were recovered. This ZrFrwas heated in a stream of dry inert gas (nitrogen) at a sufficientlyelevated temperature, about 300 C., and a period of time sufficientlylong, about 3 hours, to condition and activate the material, The meshsize distribution of the ZrF4 particles did not change substantiallyduring the latter heat treatment. An X-ray diffraction pattern of thecatalyst thus prepared showed that the 4-20 mesh catalyst comprisesmaterial of crystallite size of about 50 A., i. e. the crystallite sizewas so small as to be indicative of amorphous structure.

In the utilization of the catalysts of the invention to effectfluorination of the starting material indicated, reaction temperaturesare maintained at or above the level at which fluorination of theparticular starting compound begins to take place in the presence ofgaseous HF and the solid ZrF4. Generally speaking, in the case ofstarting materials utilizable as hereindescribed, some fluorination maybe noted at temperature as low as about 2l0 C., which temperature, it isnoted, is just above the 202-204 C. boiling point of the preferredCCl3CO'CCl3 starting material. However, reaction proceeds at a moresatisfactory rate and fluorination will generally be more complete attemperatures upwardly of about 275 C. Fluorination proceeds and yieldsof sought-for products may be realized at temperature as high as about450C.

For reasons of economy and to guard against decomposition of startingmaterial and products, higher temperatures are not particularlydesirable.

Choice of reaction temperature is determinable to a degree by the natureof the starting material employed and the nature of the sought-forproducts. Generally, in the case of starting materials containing no orsay one fluorine atom, and only moderate further fluorination is sought,relatively low temperatures may be used, but if good conversion or ahigher degree of fluorination is desired, higher reaction temperaturesare in order. Similarly, in the case of starting materials of higherfluorine content, higher temperatures are needed to effect furtherfluorination. For example, to effect formation of products predominantlydifluorotetrachloracetone, temperatures in the approximate range of300350 C. are effective. For formation of products containing arelatively small amount of difluorotetrachloroacetone and largerquantities of trifluorotrichloroacetone and tetrafluorodichloroacetone,e. g. trifluorotrichloroacetone predominating, tem-.

peratures in the range of about 350400 C. are more satisfactory. Inoverall general practice, temperatures in the range of about 300400 C.are preferred.

The molar ratio of HP to starting material is determined largely by theamount of fluorine desired in the sought-for product. That is, if ahigher fluorinated product is desired and the starting material containsno fluorine or only a small proportion and contains a relatively largenumber of chlorine atoms to be substituted, corresponding large amountsof HF are introduced into the reactor with the starting material. Onemol of HF for each atom of other halogen to be substituted is thetheoretical amount. On the other hand, from a practical point of view itis highly desirable to maintain the ratio of HF to organic startingmaterial sufliciently low so that a high percentage utilization offluorine will be obtained thereby simplifying the potentially difficultproblem of recovering HF from the product mixture, since recycling ofunreacted starting material is more practicable than recovery of un- Ireacted HF. Generally, in manufacture of products containing not morethan three fluorine atoms, preferably a deficiency of HF is employed,and in the case of production of monofluoropentachloroacetone, thequantity of HF used may be as little as 50% of theory. On the otherhand, when making tetrafluorodichloroacetone, amounts of HF employed arepreferably from about theoretical to 25% in excess of theory.

Time of contact of starting material with zirconium fluoride catalystmay be varied to some extent without noticeable sacrifice inadvantageous high process efiiciency. However, if contact time isexcessive (low space velocities), the capacity of the reactor is low. Onthe other hand, if contact time is excessively short (high spacevelocities), the reaction of starting material to form desired productmay be incomplete, thereby entailing possible high cost of recoveringand recycling unreacted material to subsequent operation. Accordingly,the time of contact is determined usually by balancing economicadvantages of high throughput obtained at short contact times againstthe cost of recovery of unreacted starting material. In general, contacttime is lessthan about 60 seconds, and preferably contact time is lessthan about 20 seconds. In a particular operation the rate of flow ofstarting material through the reaction zone is dependent upon variablessuch as scaleof operation, quantity of catalyst in the reactor, startingmaterial used, product made, and specific apparatus employed. For agiven operation, optimum conditions as temperature, quantity of HF, andcontact time may be best determined by test run;

Generally, the process of the invention is carried out by contacting thestarting compound with the ZrFr catalyst at temperature at whichfluorination takes place in the presence of gaseous HF. Operations maybe suitably carried out by introducing a gaseous mixture of reactantsinto .a reaction zone containing the catalyst and heating said purposesof temperature control, the reactants may be diluted with other gaseousmaterial, e. g. an inert gas such 'as nitrogen, and the mixture of suchinert gas and reactantsintroduced into the reaction zone. Atmosphericpressure operation is preferred but the reaction may, if desired, becarried out at superatmospheric orsubatmospheric pressure. 7

a Representative products which may be made in accordance with theinvention are as follows:

Monofluoropentachloroacetone: CFCl-z.CO.CCla.-B. P.

Trifiuorotrichloroacetone: CCI2F.CO.CC1F2B. P. aboutTetrafluorodichloroacetone:

about 44 C.

and the invention also provides for manufacture of C2F3Cl3=CO, e. g.mixtures of CFs.CO.CCls I CClzF.CO.CClF2 and containing e. g. about 25(weight) percent of the former and of the latter; and for manufacture ofOzF2Cl4'=CO, e. g. mixtures of CCI2F.CO.CC12F CCIFLCOCC], B. P. 118-122c.

and containing e. g. about equal weight parts of each; the foregoingmixtures and the CF3.CO.CCls and CClFaCOLCCls constituents per se beingnew materials not heretofore known. a

The sought-for productin the gas stream exiting the reaction zone may berecovered in any suitablemanner as by condensation and subsequentfractional distillation. The identity and amount of product in the reactor exit gas stream may be determined by fractional distillationand/or conventional infrared analytical technique. The gaseous productmay be condensed in a vessel maintained at a temperature substantiallybelow the boiling point of the lowest boiling material present, e. g. byindirect cooling of the gas in a bath of acetone and carbon dioxide ice.The particular products recovered depend, as indicated above, uponstarting material and reaction conditions such as temperature, molarratio of the reactants, etc. Substantially pure product may be recoveredby distillation of condensates obtained above, and unreacted halogenatedcompound starting material recycled to subsequent operation.

Any suitable chamber or reactor tube constructed of inert material maybe employed for carrying out the reaction provided the reaction zone isof suflicient length and cross-sectional area to accommodate therequired amount of catalyst necessary to provide adequate gas contactarea and at the sametime afford sutficient free space for passage of thegas mixture at an economical rate of flow. Materials such as nickel,graphite, Inconel and other materials resistant to HF may be suitablefor reactor tubes. Externally disposed reactor tube heating means suchas electrical resistance heaters may be used for heating purposes.

The following examples illustrate practice of'the invention, parts andpercentages being by weight unless otherwise indicated:

Example 1 About cc.-(4 to 14 mesh) of zirconium fluoride catalyst,prepared by procedure substantially described in Example A above,activated just before use by heating' for 3 hours in a stream ofnitrogen at about 300 C.

and composed of crystallites of size below about 40 A., were arranged ina fixed bed supported in a vertically disposed one inch inside diameternickel tube 30 inches long. The tube was externally electrically heatedover a length of 24 inches and the tube ends were fitted with pipeconnections for the inlet and outlet of a gas stream. Suitablethermocouples were arranged internally in the, catalyst bed andexternally of and adjacent to the nickel tube and inside the furnace.620 parts of. hexachloroacetone were vaporized and mixed with 216 partsof anhydrous HF, and the mixture was introduced into the feed end of thenickel tube and passed through the bed of ZrF4 catalyst during a periodof six hours. By adjusting the electrical heaters thereby to control therate of heat input in the gas stream, the temperature of the reactiontube was maintained at about 360 C. as measured internally of the tube.Gaseous products of the reaction were withdrawn from the discharge endof the nickel tube, cooled to minus 78 C. in a cold trap injwhich allproducts except HCl were condensed. Uncondensed HCl exiting the trap wastaken up in water. The condensate collected in the trap was distilledthru a fractionating column, and after distilling oil unreacted HF therewere obtained 108 parts of tetrafiuorodichloroacetone, CClF2.CO.CClF2;281 parts of triiluorotrichloroacetone in the form of a mixturecontaining about 25% (weight) CF3.CO.CC13 and 75% CClFaCOlCCbF; and 60parts of difiuorotetrochloroacetone in the form of a mixture containingabout equal parts by weight of CC12F.CO.CC12F and CClF2.CO.CCls. About64% of the HF charged had reacted with equivalent formation of HCl.

Example 2 About 400 cc. of a ZrF4 catalyst (4 x 14 mesh), prepared byprocedure substantially as described in Example A above and comprisingcrystallite material of average size below 150 A., were charged into afluorination reactor. During about 5 hours 2.47 mols of vaporoushexachloroacetone and 12.2 mols of anhydrous HF gas were simultaneouslypassed thru the reactor. Average catalyst bedtemperature during the runwas about 340 C., and average contact time was about 2 seconds. 4.88mols of HCl were formed, indicating that 1.98 mols of HF had reacted permol of hexachloroacetone. The molecular composition of the organicproducts recovered was as follows:

Percent Trifiuorotrichloroacetone CClFz.CO.CClzF 36.8

Difiuorotetrachloroacetone: about equal parts of CClF2.CO.CCls andCC]2F.CO.CC12F 47.0

Monofiuoropcutachloroacetone CCl2F.CO.CCl3 16.2

The following examples are illustrative of some uses of the herein newcompounds. In the processes of these particular examples it appears thatreactions involved proceed 'in accordance with the followingillustrations: EQUATION A CC1Fz.CO.CCl2F+NaOH CClFz;COONa+CHC12FEQUATION B CClF2.CO.CC1zF+4NaOH CClF2.COONa-}-CO+2NaCl+NaF+2H2O C.. overa period of about 60 minutes. During incorporation of the NaOH solution,the reacting mass was maintained at a temperature of about 40 C. Afterabout an- 5 ter,

other hour, during which temperature did not exceed 40 C., the reactionmass was cooled toabout 25 C., permitted to settle, and about 96 g. ofchloroform were separated by decantation. The chloroform recoveredamounted to about of theory in accordance with Equation A above. Theremaining aqueous reaction prod uct was found to contain about 0.62 molof NaCl. In this run about 20% of the original ketone had been subjectedto halogen attack resulting in formation of lay-products other than ahaloform such as CO, NaCl, NaF, and 1120, as indicated by Equation 13.This reaction product con taining CClzRCOONa in solution was treatedwith about 1.5 mols of 100% H2504, in the form of 96% strength sulfuricacid. About 200 grams of benzene were added to extract CClzECOOl-I. Theextract was dried by azcotropic distillation of some of the benzene andall of the water present, and the dried benzene-CClzECOOH extract wasfractionally distilled to recover CClzECOOH. (B. P. 162 C.) as overhead.The quantity of CClzRCOOH recovered amounted to 95% of theory.

Example 4 To one mol of CClzFCOCClzF (B. 1. 118-122 C.) were added 2mols of NaOH, as a 20% strength water solution, over a period of aboutminutes. During addition of the NaOH, temperature of the mass in the reaction vessel was maintained at about 20 C. About 70 (0.6711101) ofCHClzF (13.1. 8.9 C.) were evolved in the course of the reaction andwere recovered in a Dry-Ice trap. About 2 mols of 100% H2804, as a 96%sulfuric acid solution, were added to the mass in the reaction vessel.Similarly as in Example 3, the CClzFCOOH formed by acidification of theCClzRCOONa was benzene extracted, the extract dried, and the quantity ofCCl2F.COOH recovered on final fractional distillation amounted to 93% oftheory.

Example 5 One mol of CClF2.CO.CCls (B. P. about 120 C.) was slowly addedwhile agitating over a period of about 90 minutes to 1.8 mols of NaOl-l,as 20% strength water solution. During addition of the NaOH solution,the reaction vessel was cooled externally to maintain reactiontemperature at about 25 C. After succeeding 1 hours, the liquid phasesformed in the reaction vessel were separated, and about 0.75 mol ofCHCls was recovered. Analysis of the remaining aqueous phase showed thepresence of 0.76 mol chloride ion, indicating that about 25% of theketone starting material had been subjected to halogen attack. Thisaqueous phase containing CClFz.COONa in solution was acidified byaddition of 2 mols of 100% H2504, as 96% sulfuric acid. CClFaCOOI-I wasextracted from the acidified liquor with benzene as in Example 3, andCClFz.COO1-I (B. P. 121 C.) was recovered from the dried extract inamount equal to 95% of theory.

Example 6 One mol of CC1F2.CO.CCl2F (B. P. 84.2 C.) was added slowlyover a period of about 120 minutes to 220 g. of powdered 85% KOH (3.3mols of KOH) suspended in about 500 g. of benzene. During incorporationof the KOH, the mass was agitated, and external cool- 'ing of thereaction vessel was such as to maintain temperature of the reacting'massat about 30-40 C. Carbon monoxide and CHClzF were evolved and about 0.4mol of CHClzF was collected in a Dry-1ce trap. The bulk of the benzenewas decanted off from the reacted mass, and the solid relativelyslurry-like potassium salt product CClFz.COOK was dissolved by additionof about 100 g. of water. Analysis of the resulting aqueous solution forchloride and fluoride ions showed that about 60% of the original ketonehad been subjected to halogen attack. The aqueous solution was acidifiedby addition of about 400 g. of 100% H2304, as 96% sulfuric acidsolution. Following benzene extraction, azeotropic removal of waranddistillation similarly as in Example 3,

9 CClFz.COOH (B. P. 121 C.) was recovered in amount equal to 92% oftheory.

Example 7 One mol of CClF2.CO.CClF2 (B. P. 44 C.) was added dropwiseduring one hour to a cooled agitated suspension of 160 g. powdered NaOH(4 mols) in 500 cc. of benzene. Reaction temperature was maintained atabout 40 C. Carbon monoxide was evolved. After a further period of about2 hours, to permit completion of reaction, the reaction product wascooled to about 20 C. and filtered. The solids were dried by heatingunder vacuum at about 50 C. Analysis showed that the dried solidscontained 1.8 mols of NaF and 0.9 mol of NaCl. The solid reactionproduct containing CClFnCOONa was treated with 600 g. of 100% H2804 (6.1mols), as 96% sulfuric acid solution, and CClF2.COOH and small amountsof HF and HCl were distilled out. Redistillation of the crude CClF2.COOHgave 122 g. of

CCIF2.COOH

equal to 94% of theory.

Example 8 10.25 mols (54 g.) of CF3.CO.CC13, B. P. 83.5-84.5 C., weremixed with cooling with g. of water. To this mixture cooled in an icebath was slowly added 0.5 mol (20 g.) of NaOH dissolved in 60 g. ofwater over a period of about 30 minutes. During incorporation of theNaOH solution, the reaction mass was maintained at a temperature ofabout -15 C. After the NaOH solution had been added, temperature wasraised to about 50 C. and maintained at that point for about an hour tofacilitate completion of reaction. The reaction mass containingCF3.COONa in solution after cooling to about room temperature, wastreated by slow addition of 350 g. of 96% sulfuric acid. Chloroform andCF3.COOH were distilled out, and fractionation of the crude condensatethus obtained gave 27 g. (92% of theory) of CF3.COOH, B. P. 7173 C., and24 g. of CHCl3 (80% of theory).

The hereindescribed fluorochloro acids are known in the art. The monoand tri fluoro acids are suitable for use as esterification catalysts,and the mono and di fluoro acids constitute eflective solvents forcellulose.

Subject matter of Examples 3-8 inclusive is disclosed and claimed in ourcopending application, Serial No. 494,236, filed of even date herewith.

This application is a continuation in part of our copending applicationSerial No. 411,027, filed February 17, 1954, now abandoned.

We claim:

1. The process for making a perchlorofluoro acetone which processcomprises introducing a substantially anhydrous gas-phase mixture of HFand a starting materialsaid starting material comprising aperhalogenated chloroacetone containing zero to not more than 3 fluorineatoms and wherein all halogens are of the group consisting of chlorineand fluorine-into a reaction zone containing substantially anhydrouszirconium fluoride catalyst having crystallite size not substantiallygreater than about 400 Angstrom units radius and having been derived byreaction of substantially anhydrous ZrCl4 and substantially anhydrousHF, heating said mixture in said zone in contact with said catalyst atfluorination temperature in the approximate range of 210450 C. to effectfluorination of substantial amount of said starting material and for- 10mation of a product comprising a perchlorofluoroacetone containing atleast two chlorine atoms, and wherein the fluorine content is greaterthan that of said starting material, and withdrawing said product fromsaid zone.

2. The process of claim 1 in which fluorination temperature isapproximately in the range of 300-400 C.

3. The processof claim 1 in which the catalyst crystallite size is notsubstantially greater than about Angstrom units radius.

4. The process for making a perchlorofluoroacetone which processcomprises subjecting a starting materialsaid starting materialcomprising a perhalogenated acetone containing zero to not more than 3fluorine atoms and wherein all halogens are of the group consisting ofchlorine and fluorine-in a reaction zone to the action of substantiallyanhydrous HF, while in the presence of substantially anhydrous zirconiumfluoride catalyst of crystallite size not substantially greater than 400Angstrom units radius and having been derived by reaction ofsubstantially anhydrous ZICl and substantially anhydrous HF, at elevatedtemperature high enough to effect fluorination of substantial amount ofsaid starting material and formation of a product comprising aperchlorofluoroacetone and containing at least two chlorine atoms andwherein the fluorine content is greater than that of said startingmaterial.

5. The process for making a perchlorofluoroacetone which processcomprises introducing a substantially anhydrous gas phase mixture of HFand hexachloroacetone into a recation zone containing zirconium fluoridecatalyst having crystallite size not substantially greater than about400 Angstrom units radius and having been derived by reaction ofsubstantially anhydrous ZrClr and substantially anhydrous HF, heatingsaid mixture in said zone in contact with said catalyst at fluorinationtemperature in the approximate range of just above the boiling point ofhexachloroacetone to 450 C., to efiect fluorination of substantialamount of said hexachloroacetone and formation of a product comprising aperchlorofluoroacetone containing at least two chlorine atoms, andrecovering perchlorofluoroacetone from said product.

6. The process for making perchlorofluoroacetone which process comprisesintroducing a substantially anhydrous gas-phase mixture of HF andhexachloroacetone into a reaction zone containing substantiallyanhydrous zirconium fluoride catalyst having crystallite size notsubstantially greater than about 150 Angstrom units radius and havingbeen derived by reaction of substantially anhydrous ZrCLi andsubstantially anhydrous HF, heating said mixture in said zone in contactwith said catalyst at fluorination temperature in the approximate rangeof 300-400 C. to effect fluorination of substantial amount of saidhexachloroacetone and formation of a product comprising aperchlorofluoroacetone containing at least two chlorine atoms,withdrawing said product from said zone,and recoveringperchlorofluoroacetone from said product.

References Cited in the file of this patent UNITED STATES PATENTS2,423,045 Passino et al June 24, 1947 2,533,132 McBee et al Dec. 5 19502,567,569 McBee et al Sept. 11, 1951 2,614,129 McBee et a1. Oct. 14,1952 2,709,688 Bandes et a1. May 31, 1955

1. THE PROCESS FOR MAKING A PERCHLOROFLUORO ACETONE WHICH PROCESSCOMPRISES INTRODUCING A SUBSTANTIALLY ANHY DROUS GAS-PHASE MIXTURE OF HFAND A STARTING MATERIALSAID STARTING MATERIAL COMPRISING APERHALOGENATEDCHLOROACETONE CONTAINING ZERO TO NOT MORE THAN 3 FLUORINE ATOMS ANDWHEREIN ALL HALOGENS ARE OF THE GROUP CONSISTING OF CHLORINE ANDFLUORINE-INTO A REACTION ZONE CONTAINING SUBSTANTIALLY ANHYDROUSZIRCONIUM FLUORIDE CATLAYST HAVING CRYSTALLITE SIZE NOT SUBSTANTIALLYGREATER THAN ABOUT 400 ANGSTROM UNITS RADIUS AND HAVING BEEN DERIVED BYREACTION OF SUBSTANTIALLY ANHYDROUS ZRCL4 AND SUBSTANTIALLY ANHYDROUSHF, HEATING SAID MIXTURE IN SAID ZONE IN CONTACT WITH SAID CATALYST OFFLUORINATION TEMPERATURE IN THE APPROXIMATE RANGE OF 210-450*C. TOEFFECT FLUORINATION OF SUBSTANTIAL AMOUNT OF SAID STARTING MATERIAL ANDFORMATION OF A PRODUCT COMPRISING A PERCHLOROFLUOROACETONE CONTAINING ATLEAST TWO CHLORINE ATOMS, AND WHEREIN THE FLUORINE CONTENT IS GREATERTHAN THAT OF SAID STARTING MATERIAL, AND WITHDRAWINHG SAID PRODUCT FROMSAID ZONE.